2道GMAT数学题1,Afterdrivingtoariverfotparkinglot,Bobplanstorunsouthalongtheriver,turnaround,andreturntotheparkinglot,runningnorthalongthesomepath.Afterrunning3.25milessouth,hedecidestorunforonly50minutesmore.If

Question

2道GMAT数学题
1,After driving to a riverfot parking lot,Bob plans to run south along the river,turn around,and return to the parking lot,running north along the some path.After running 3.25 miles south,he decides to run for only 50 minutes more.If Bob runs at a constant rate of 8 minutes per mile,how many miles farther southcan he run and till be able to return to the parking lot in 50 minutes.(这道题的题意完全不理解,)
A1.5 B 2.25 C3.0 D 3.25 E .75
2,If Q is an odd number and the median of Q consecutive integers is 120,what is the largest of these integers.题意不清
A (Q-1)/2+120 B Q/2+119 C Q/2+120 D (Q+119)/2 E (Q+120)/2

Answer 1

鲍勃开到一个临河的停车场后,决定先沿着河继续往南开,然后掉头沿来时的路向北返回停车场.鲍勃向南开了3.25英里之后,他决定只继续开50分钟.假如鲍勃开车的速度为8分钟开一英里,那么他还能向南开多久,才能确保在50分钟内返回到停车场?
 
8分钟1英里,就是每分钟0.125英里.设往南开x英里,有方程x + 3.25 = 50×0.125 - x,解得x = 1.5英里
所以选A.
 

假如Q是个奇数,Q个连续整数的中值为120,那么连续整数中最大的数是多少?
应当是120 + (Q-1)/2.选A.

都是些很基础的数学题啊……